There are so many variables there the question is pretty hard to answer. We don't know the size of the composition, the number of effects and most importantly your computer, processing power and RAM.
There are lot of threads dealing with speeding up AE here at the Cow, so you might want to do a search. But if you don't have a fast computer there is not a lot you can do to make things much faster.
Johnny Cuevas, Editor
"I have not failed 700 times. I have succeeded in proving that those 700 ways will not work. When I have eliminated the ways that will not work, I will find the way that will work."
---THOMAS EDISON on inventing the light bulb.